Brake



' l l 1,634,368 July 5,-1927. L. E LA BRIE l l' BRAKE` Filed Jam.y 11,1926 2 sheets-511661 1 lll-1 ,fp

INVENTOR 'LUDGBR E. LABRLE ATTORNEY Patented July 5, 1927.

UNITED STATESv LUDGER ELIZE LA BRIE, OFSOUTH BEND, INDIANA, ASSIGNORPATENT OFFICE.

T BENDIX :BRAKE COMPANY, 0F GHICAGO, ILLINOIS, A. CORPQRATION OFILLINOIS. I

BRAKE.

Application mea January 11, 1926. seal No. 80,396.l

This invention relates to brakes, -and ist illustrated as einbbdied inan internal eX- panding front wheel automobile brake.

An object of the invention is to provide a novel positioning orcentering device for the shoes, or other friction device, utilizing alever preferably having a. wedging actionto tension a spring whichserves to return the shoes when 'the brake is released.

Another feature of the invention relates to a novel control, especiallyadapted for use with an automobile brake, which permits the use offriction means, such as a set of connected shoes, shiftable to anchor atone end when the drum is turning in one direction and at the other endwhenA the drum is turning in the other direction, and yet which insuresthat at least when the vehicle is moving forward there will be nomovement of the anchored end awayfrom the anchor during the initial partof the brake-applying movement. This not only reduces lost motion butalso eliminates the clicking noise of one end of the friction meansre-seating itself on its anchor.

Other features relate to improved anchoring means for a brake of thistype, to a novel shoe construction, and to other new combinations ofparts and desirable particular constructions which will be apparent-mounted on pin Support 50 has `at its from the following description ofone illustrative embodiment shown in the accompanying drawings, inwhich:

Fig. l is a vertical transverse section through one front wheel andbrake, looking toward the rear of the car;

Fig. 2 is a vertical section through the brake, on the line 2-2 of Fig.1;

Fig. 3 is a partial vertical section on the line 3-3 of Fig. 1;

Fi 4 is a sectional detail on the line 4-4 of Fig. 2, showing oneanchor;

Fig. 5 is a partial section on the line 5-5 of Fig. 2,'showing thecentering lever; and

Fig. 6 is a diagram corresponding to 'a top plan view of Fig. 1, andillustrating the.

release of the outer brake on a turn.

-The brake selected for illustration includes a one-piece hub and brakedrum 10, on which an annular disk 12 carrying the rim14 is mounted. Thehub and drum 10 is rotatably mounted on the spindle 16 of a knuckle 18swivelled in one end of the front axle 9A). A backing plate 22 closingthe 34 on a pivot or other connection 36. -Cam has a flange at its endand confining the ends of the s oes against lateral movement. Just backof plates 28, shoes 24 and 26 are cut away to form notches facing towardthe.

ends of the shoes. L-shaped wear parts 38 are secured by bolts,A 40along the sides of the shoes, each with-one vleg projecting into itsnotch to form an approximately radial abutment surface anchoringagainstan adjustable eccentric anchor 42 mounted on the backing plate.

Bolts 40 also hold plates 44 for a return spring 46` connecting theshoes-and urging them away from the drum and against anchors 42. Thecentral part of spring 46 is coiled about', a pin 48 (Fig.v 1), carriedby the backing plate, thus forming a compression spring lightly clampingagainst the plate a support or bracket 50 pivotally upper -end a bearingprojecting through a somewhat larger opening in plate 22, and inWhich-is journalled a shaft E12/integral with or secured to the cam 30.

By the above-described arrangement, it will \be seen that cam 30 forcesshoes 24and 26 apart against the drum, and can shift about pivot 48 sothat shoe 24 anchors against its anchor 42 when the drum is turningclockwise in Fig. 2 (vehicle moving forward), or shoe 26 may anchoragainst its anchor 42 when the drum is turning counterclockwise in Fig.2 (vehicle moving back'- ward). Whenythe brake is released both Shoesengage the anchors 42, which, being eccentric, ma be turned to preservea predetermined c earance between the shoes and drum as the brake liningwears.

The shoes are centered when -released by a lever 54 having a doublewedge surface embracing a roller 56 on pivot pin 36 (Figs. 1 and 5). Pin36 projects through a slot 58 open sideof the drum is secured to knucklealong a chord of the backing plate, and has drum, and the friction ofthe drum is sufwashers 60 lightly clamped against opposite sides of thebacking plate by tightening a nut 62 on the end of the pin. The lever isfulcrumed on a pivot 64 adjustably clamped in a radial slot 66 in thebacking plate (Fig. 2), and is rocked when the shoes shift in. eitherdirection, by the wedging action of roller 56, in such a manner as totension a centering spring 68 connected at its ends to the free end oflever 54 and to an adjustable pin 70 carried by the backing plate. Pin36 also serves to hold the lower ends of the shoes against lateralmovement.

Shaft 52 is rocked to apply the brake by an arm 72 adjustably clamped onits end and extending toward the pivotal axis about which support 50shifts. Arm 72 is operated by means such as a lever 74 fulcrumed on axle20 for movement about a generally vertical axis. Lever 74 is shown witha ball `76 at its end engaging a plane surface on arm 72.

T prefer that the center of ball 76 should not be exactly in the axis ofpivot 48 when the brake is applied, which would permit support 50 toswing freely in either direction, but a short distance 78 (Fig. l) abovethat axis. This distance is selected so that there is no materialinterference with the vswinging of support 50 as one or the other ofshoes 24 or 26 seats on its anchor, while yet there is a suiiicientcomponent of force tending to turn support 50 about its axisso that thesupport and cam 30 move bodily forward to cause shoe 26 to engage thedrum, before cam 30 really begins to turn to urge both shoes'toward thedrum. During this time shoe 24 is held against its anchor 42, whilelever 54 'holds it away from the drum.

If at this time drum 10 is turning counterclockwise in Fig. 2, i. e. ifthe car is moving backward, further movement of lever 74 rocks cam 30 toforce both shoes against the iicient to swing support 50 back again andcause shoe 26 to seat against its anchor 42. This does not often occur,however, as usual- 1y the vehicle is moving forward when the brakes areapplied.

If the vehicle is movin forward and drum 10 in Fig. 2 is turning cockwise (the usual4 case), however, there'is no such lost motion as justdescribed. In this case, -shoe 24 remains seated against its anchor 42atv all times, and the brake is applied as smoothly and gradually as ifshoe 24 were anchored on a fixed pivot. After shoe 26 engages the drum,and as cam 30 begins to turn, shoe 26 turns circumferentially with thedrum and forces shoe 24 about anchor 42 toward the drum, against theVresistance of spring 68. This successive action of the shoes gives avery smooth and gradual application of the brake.

When the brake is used on a front wheel,

outer brake on a turn, to guard against skidding, the center of ball 76is not exactly in the swivelling axis, when the brake is applied, but isa short distance 80 of a few hundredths of an inch away from that axis,on the side next the wheel.

The result is shown on an enlarged and distorted scale in Fig. 6. WV isa line through the swivelling axis A of the wheel parallel to the wheelwhen the vehicle is running straight ahead. WL is a similar lineparallel to the wheel when it has been swivelled to turn to the left,lacing it on the outer side of the turn (the right-hand front wheel ofthe car being shown, regarding it from the drivers seat, or in theopposite direction from the point of view in Fig. l). WR is a similarline parallel to the wheel when it has been swivelled to steer to theright, placing it on the inner side of the turn.

When the wheel .is parallel to W, the joint between lever 74 and arm 72is at J, opposite axis A. When the wheel is parallel to lineWVR, on theinner side of the turn, arm 72 swings with the wheel about axis A, andtries to crowd the joint back to JR, thus slightly increasing thepressure on the brake. But when the wheel is parallel to WL, on theouter side of the turn, arm 72 swings to JL, away from lever 74, thusslightly relieving the pressure on the brake.

It will be observed that the center of ball 76 when the brake isappliedis in this particular instance immediately adjacent the intersection ofthe swivelling axis of the wheel with the pivotal axis or axis of pivot48, but

slightly above the pivotal axis and slightly outside the swivellingaxis.

V'Vhile one illustrative embodiment has been described in detail, it isnot my intention to limit the scope of the invention to that particularembodiment, or otherwise than by the terms of the appended claims.

I claim:

1. A brake com rising a friction device, in combination wit positioningmeans therefor including a lever and a art having wedging engagementlwith the ever and a spring tensioned by movement of the lever due torelative wedging movement of' the lever and said part.l

2. brake com rising a friction device, in combination wit positioningmeans therefor including a lever supported and fulcrumed separately fromthe friction device and swung by movement of the friction device and aspring tensioned'by movement of the lever due to relative movement ofthe"lever and the friction device.

3. A brake comprising a friction device lCfl iis

land an adjacent stationary support, in combination with a lever mountedon the support, a part moving with the friction device and engaging thelever, and a, spring tensioned by movement of the lever by said 4. Abrake comprising a friction device and an adjacent stationary support,in combination with a lever mounted on the support and providedvwith awedge surface, a part moving with the friction device and wedginglyengaging the lever, and a spring tensioned by movement of the lever bysaid art. p 5. A brake comprising, in combination, a friction device, a.lever having a wedge surface on one edge, a part wedgingly engaging saidsurface, the lever and said part being moved relatively to each other,to rock the lever by movement of the friction device,-

. A brake comprising, in combination, a.`

drum, a plurality of connected shoes shift able with respect to the drumvso that one shoe is anchored when the drum is turning in one directionand a different shoe is anchored when the drumis turning in the otherdirection, a support adjacent the shoes, a lever mounted on the support,means for rocking the lever when the shoes shift in either direction,and a spring tensioned by the rockingy of the lever.

8. A brake comprising, in combination, a drum, a plurality of connectedshoes shiftable with respect to the drum so that one shoe is anchoredwhen the drum is turning in one direction and a different shoe isanchoredv when the drum is turning in the other direc'- tion,'a supportadjacent the shoes, a lever mounted on the support, a lever-engagingpart shifting withlthe shoes'and arranged'to rock the lever when theshoes shift in either direction, and a spring tensioned by the rockingof the lever. I

l 9. A brake comprising, i'n combination, a

' drum, a set of floating connected shoes within the/drum havingadjacent freel ends, a floating shoe-expanding cam engaging said ends,the shoes being cut away near said ends and having abutment partsfacingtoward said ends, and a pair of fixed stops engaged respectivelyby said abutment parts and one or the other of which serves as an anchorfor all'of the Shoes.

10. A brake comprising, in combinationl a drum, an expansible frictiondevice floating within the drum having adjacent free ends, a floatingexpanding cam engaging said ends, the friction device being cut awaynear said ends and having abutment parts facing toward said ends, and apair of fixed stops engaged respectively by said abutment parts and oneor the other of which serves as an anchor for the friction device.

11. A brake shoe having a cam follower part at one end and cut out toform a notch adjacent said end with a separate abuti'nent part crossingthe wall of said notch and facing toward said end.

l2. A brake shoe having a cam follower part at one end and cut out toform a notch adjacent said end with an approximately radial L-shapedabutment part forming the wall of said notch facing toward said end and'secured with one leg overlapping the side of the shoe and with the otherprojecting into the notch to form said wall.

18. A wheel having a brake including a drum and friction vmeansshiftablc to anchor at one end or the other according to the directionof rotation of the drum, in combination with a floating brake-applyingdevice acting on said ends, and means for operating said device arrangedto shift it bodily when the brake is first applied to force one end ofthe friction means against the drum -before sufficient force is appliedto the other end to cause it to move toward the drum.

d4. A wheel having a brake including a drum and friction -meansshiftable to anchor at one end or the other according to the directionof rotation of the.' drum, in combinationwith a floating brake-applyingdecient-force is applied to the other end ,to

cause it to -move toward the drum, said component being small enough tobe readily overcome by the friction ofthe drum when it turns in adirection to anchor said device at its first end.

drum and friction means shiftable to anchor at one end or the otheraccording to the direction of rotation of the drum, in coinbination witha floating pivotally-mounted brake-applying device acting on said ends,an arm for operating sa'id device, and applying means acting on the armlin a manner to l5. A wheel having a brake including a rock it to expandthe friction means but engaging it at such a point as to swing it aboutits pivot when the brake is Vfirst applied.

16. A wheel having a brake including a drum and friction means, incombination with a Heating piVotally-mounted brake-applying deviceacting on said means, an arm for operating said device, and 1 applyingmeans acting on the arm in a manner to rock it to expand the frictionmeans but engaging it at such a point as to swing it about its pivotwhen the brake is first applied.

17. A Wheel having a brake including a drum and friction means, incombination with a pivotally-monnted support carrying a brake-applyingdevice including an arm extending toward the pivotal axis, and apply.

ing means engaging said arm immediately adjacent that axis on the sidenext the brake- -applying device so as to have a component 0f forcetending to swing the support about the pivotal axis.

18. A Wheel having a brake including a drum and friction means, incombination 4with a pivotally-mounted supportcarrying a brake-applyingdevice including an arm extending toward the pivotal axis, and anoperating lever having a part engaging sal-d arm immediately adjacentthat axis on the side next the brake-applying device so as to have acomponent of force lending to swing the support about the pivotal axis.

l 19. A brake comprising, in combination, a drum, a set of connectedslices engageable with the drum and shiftable to anchor on one shoe Whenthe drum is turning in one direction and on a different shoe when thedrum drum, a floating friction device engageable with the drum andshiftable to anchor at one end When the drum is turning in one directionand at the other end when the drum is turning in the opposite direction,and brake-applying means acting on both ends and shiftable to ermitanchoring at either end but arranged) to force one of the ends againstthe drum before initiating applying movement of the other end.

21. A brake comprising, in combination, a drum, a plurality of connectedshoes shiftable with respect 1 the drum so that one shoe is anchoredWhen the drum is turning in one direction and a different shoe isanchored when the drum is turning in the otherdirection, a supportadjacent the shoes, a lever mounted lon the support, means for rockingthe lever when the shoes shift in either direction, and means to resistrocking of said lever and tending to return it to its original position.

In testimony whereof, I have hereunto signed my naine.

LUDGER ELIZE LA BRIE.

